EXOSTATION is a project aiming at building a complete haptic control station, which allows the operator wearing an exoskeleton-based haptic interface for the human to remotely control a virtual slave robot. The video presents the results achieved with the final system. It is composed of four main components. A human-arm exoskeleton used as a master haptic interface, its controller, a simulated virtual slave robot and a visualization tool. Demonstration scenarios are presented in the video and show the capabilities of the system.

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In this paper it is shown how variation of the kinematic structure of an exoskeleton and variation of its fixation strength on the human limb influences objective task performance metrics, such as interface load, tracking error and voluntary range of motion in a signal tracking experiment.

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One of the key features of upper limb exoskeletons is their ability to take advantage of the human arm kinematic redundancy in order to modify the subject’s joint dynamics without affecting his/her hand motion. This is of particular interest in the field of neurorehabilitation, when an exoskeleton is used to interact with a patient who suffers from joint motions desynchronization, resulting e.g. from brain damage following a stroke. In this paper, we investigate this problem from the robot control point of view. A first general controller is derived which uses viscous force fields in order to generate joint torques counteracting any velocities that are perpendicular to a given set of constraints. In order to minimize energy dissipation, a second controller is proposed that still uses viscous force fields, but in a way that the mechanical power dissipated by the viscous control is null at any time. This controller does not impose any trajectory to the hand and the robot only moves in response to the forces generated by the patient. This approach is experimented on a 4-DOF exoskeleton with a healthy subject. Results exhibit the basic properties of the controller and show its capacity to impose an arbitrary chosen joint constrain for 3-DOF pointing tasks without constraining the hand motion.

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An exoskeleton robot is an external structural mechanism with joints and links corresponding to those of the human body. When it is worn, it transmits torques from actuators through rigid exoskeletal links to the human joints. We have been developingexoskeleton robots for assisting the motions of physically weak persons such as elderly or disabled in daily life. In this paper, we propose an electromyogram (EMG) based control (i.e., control based on the skin surface EMG signals of the user) for theexoskeleton robot to assist physically weak person’s lower-limb motions. The skin surface EMG signals are mainly used as the input information for the controller. In order to generate flexible and smooth motions and take into account the changing EMG signal levels according to the physical and psychological conditions of the user, fuzzy-neuro control method has been applied for the controller. The experimental results show the effectiveness of the designed EMG-based controller for the power-assist.

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Exoskeleton systems that can enhance people’s performance or assist disabled people have been investigated in recent years. However, most exoskeletons utilize DC motors with batteries as the driving source. While the motors require a lot of power, the working time of the exoskeletons is a limiting factor for the implementation of mobile exoskeletons. This paper proposes a new legexoskeleton that uses a magnetorheological (MR) actuator to provide controllable assistive torque. The designed MR device can function as a brake or clutch according to the working states of the user. When adjustable passive torque is preferred, the MR device will work as a brake, thus only very low power is consumed; when active torque is required, the MR device will work as a clutch, which transfers the torque generated by the motor to the user’s leg. The working states of the knee joint are determined by measuring the knee joint angle and the floor reaction force. Utilizing the MR actuator, the exoskeleton will be more energy efficient.

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